In medical field it is very often necessary to precisely position a medical device through a needle tip at a particular part of the body or an organ deep inside the body. This is required for obtaining tissue samples or for delivering drugs or for therapeutic/palliative aspiration of fluid collections or any such procedure.
This can be done percutaneously under image guidance obtained from cross sectional imaging devices such as ultrasound/CT scan/MRI scan etc. Image guidance is required to select least harmful path for the needle, so as to avoid vital organs and structures such as blood vessels, bowel etc. The needle can be placed free hand at an approximately correct angle by trial and error. This can also be better done by using needle guiding devices that can guide the needle in the precise direction so as to reach the precise point in the body.
These difficult and critical at time life saving operations/procedures require precise placement of needle/medical devices at precise points or locations in the body while avoiding damage to other delicate organs, tissues, blood vessels etc. Although it is possible to determine exact location using various electronic, sonic or other techniques, guiding the needles to that precise point by free hand is by trial and error and often requires multiple attempts. At times despite multiple attempts it may not be possible to place the needle or such medical device in the desired precise point in the body. At times multiple attempts of passing the needle may cause serious life threatening complications of internal bleeding and/or damage to vital organs in the path of the needle or such device.
There are devices available for guiding the needle in a precise direction under ultrasound guidance. There are also devices available for guiding the needle for brain interventions through drilled holes in the skull. However devices available for guiding the needle for brain interventions are not suitable/compatible for use in other parts of the body.
In the modern era of technology various advanced techniques such as CT and MR scanning are available for precise identification of locations needing treatment through placement of needles/medical devices through the needles or for obtaining tissue samples/body fluids. However a universal device capable of using these imaging techniques for precise placement of needles/medical devices through the needles any where in the body is not presently known and hence there is a need to develop such device.
The only reference available in respect of stereo tactic device in medical field is that of a device used for brain surgery/interventions that I could come across is titled frame for stereotactic surgery. The said device is described in U.S. Pat. No. 4,706,665 to Kasim I Gouda dated 17 Nov. 1987. The device provided by the abovementioned U.S. patent cannot be used on any other part of the body as it has been designed for brain surgery/interventions only.
The main object of the present invention is to provide an image guided stereo tactic device for needle/medical device placement that could be used for interventions in the entire of the body including brain.
Another object is to provide the said device which is compatible with both CT and MRI scan techniques and environment.
None of the existing stereotactic biopsy devices are capable of being used in body part affected by respiratory movement. In order to prevent damage to body organs and tissues in the path of the needle during respiratory movements it is mandatory to allow free movement of the needle or such device during breathing.
The present invention provides a stereotactic device that obviates the above limitations by allowing the parts used to support the needle to fall away from the needle, once the needle is placed in side the body.
In particular aspect of the present invention the device comprises a base plate at the bottom of the device with a supporting ring that fits in the base plate, an arc for needle guide, a screw and a pin to fix the supporting ring and arc and a needle guide.